Procarbazine side effects: what 4,488 FDA adverse event reports show
Drug class
Not stated in label
Label matched
Procarbazine Hydrochloride (Matulane)
Who reports
4,488 reports · 28% serious · 323 with death outcome · 45% female
Used for
Matulane is indicated for use in combination with other anticancer drugs for the treatment of Stage III and IV Hodgkin's disease. Matulane is used as part of the MOPP (nitrogen mustard, vincristine, procarbazine, prednisone) regimen.
What it is
DESCRIPTION Matulane (procarbazine hydrochloride), a hydrazine derivative antineoplastic agent, is available as capsules containing the equivalent of 50 mg procarbazine as the hydrochloride.
Boxed warning
It is recommended that MATULANE be given only by or under the supervision of a physician experienced in the use of potent antineoplastic drugs. Adequate clinical and laboratory facilities should be available to patients for proper monitoring of treatment.
Causality screen of the 35 strongest signals
What the badges mean
- Labeled adverse reaction The exact term appears in the label's warnings or adverse-reactions sections: a known, expected effect. The FAERS signal confirms the label rather than discovering anything.
- Labeled (related wording) The label describes this effect under different wording (e.g. 'neutropenia' for 'neutrophil count decreased'). Treated as known.
- Reporting / coding artifact An administrative, monitoring or exposure term (product issue, off-label use, 'test normal', overdose...). Not a biological reaction; a high PRR here reflects how reports are coded.
- Lab value / disease marker A laboratory result, investigation or disease-activity marker (antibody positive, CRP abnormal, swollen joint count) not described in the label. These usually mirror the monitored disease or testing protocol rather than a drug effect; not screened further.
- Not in label — unassessed Not found in the label text, not an artifact pattern. This is a genuine candidate for a formal causality assessment (Bradford Hill / WHO-UMC); it has NOT had one here.
Strongest disproportionality signals
Flagged terms (PRR ≥ 2, χ² ≥ 4, n ≥ 10), ranked by PRR; infinite PRRs (no comparator reports) excluded. The EBGM column is a second, shrinkage-based estimate (MGPS) with its 5th percentile EB05 and the BCPNN IC025; a pair flagged by PRR alone is marked PRR-only and should be read as fragile. The strata column recomputes the PRR on serious reports only and flags pairs whose reports are unusually skewed by sex or come mostly from consumers rather than clinicians. 19 further terms are in the interactive explorer. Reaction links open the term's cross-drug page.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Blood count abnormal | 132 | 40.4 34.2–47.9ROR 41.6 · χ² 4,998 / p <1e-300 | 39.9 EB05 34.5 · IC025 +4.8 3/3 methods agree | Lab value / disease marker | serious PRR 9.8 | no trial data cached |
| Full blood count abnormal | 39 | 17.3 12.7–23.7ROR 17.5 · χ² 582 / p 6e-129 | 17.1 EB05 13.0 · IC025 +3.3 3/3 methods agree | Lab value / disease marker | serious PRR 3.7 · ♀ 67% (drug 45%) · 79% consumer | no trial data cached |
| Hepatic cytolysis | 42 | 16.1 11.9–21.8ROR 16.2 · χ² 578 / p 4e-128 | 15.9 EB05 12.2 · IC025 +3.3 3/3 methods agree | Not in label — unassessed | serious PRR 33.6 · 100% clinician | no trial data cached |
| Platelet count decreased | 239 | 10.5 9.3–11.9ROR 11.0 · χ² 2,051 / p <1e-300 | 10.4 EB05 9.3 · IC025 +3.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 2.4 | no trial data cached |
| White blood cell count decreased | 229 | 9.9 8.7–11.2ROR 10.4 · χ² 1,824 / p <1e-300 | 9.8 EB05 8.7 · IC025 +3.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 4.6 | no trial data cached |
| Myelodysplastic syndrome | 28 | 9.1 6.3–13.1ROR 9.1 · χ² 192 / p 5e-44 | 8.3 EB05 5.9 · IC025 +2.4 3/3 methods agree | Not in label — unassessed | serious PRR 18.4 · 92% clinician | no trial data cached |
| Nerve injury | 21 | 8.8 5.7–13.5ROR 8.8 · χ² 138 / p 5e-32 | 7.8 EB05 5.2 · IC025 +2.2 3/3 methods agree | Not in label — unassessed | serious PRR 1.1 | no trial data cached |
| Polyneuropathy | 15 | 5.9 3.6–9.8ROR 5.9 · χ² 56 / p 3e-14 | 5.1 EB05 3.3 · IC025 +1.5 3/3 methods agree | Not in label — unassessed | serious PRR 12.5 | no trial data cached |
| Nausea | 973 | 5.8 5.5–6.1ROR 7.1 · χ² 3,974 / p <1e-300 | 5.7 EB05 5.4 · IC025 +2.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 0.7 | no trial data cached |
| Constipation | 265 | 5.7 5.1–6.4ROR 6.0 · χ² 1,038 / p 4e-228 | 5.7 EB05 5.1 · IC025 +2.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 1.1 | no trial data cached |
| Red blood cell count decreased | 31 | 5.1 3.6–7.2ROR 5.1 · χ² 97 / p 3e-23 | 4.7 EB05 3.5 · IC025 +1.6 3/3 methods agree | Lab value / disease marker | serious PRR 0.9 | no trial data cached |
| Fatigue (tiredness) | 829 | 5.0 4.7–5.3ROR 5.9 · χ² 2,739 / p <1e-300 | 5.0 EB05 4.7 · IC025 +2.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 0.6 | no trial data cached |
| Stomatitis (mouth sores) | 63 | 4.9 3.8–6.2ROR 4.9 · χ² 189 / p 2e-43 | 4.7 EB05 3.8 · IC025 +1.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.4 | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 132 | 4.6 3.8–5.4ROR 4.7 · χ² 365 / p 1e-81 | 4.5 EB05 3.9 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 4.8 | no trial data cached |
| Blood test abnormal | 13 | 4.3 2.5–7.4ROR 4.3 · χ² 30 / p 2e-8 | 3.8 EB05 2.4 · IC025 +1.0 3/3 methods agree | Reporting / coding artifact | serious PRR 1.1 | no trial data cached |
| Thrombocytopenia (low platelets) | 100 | 4.2 3.5–5.1ROR 4.3 · χ² 241 / p 1e-54 | 4.1 EB05 3.5 · IC025 +1.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.0 | no trial data cached |
| Disease progression | 95 | 3.8 3.1–4.6ROR 3.8 · χ² 191 / p 9e-44 | 3.7 EB05 3.1 · IC025 +1.6 3/3 methods agree | Reporting / coding artifact | serious PRR 5.9 | no trial data cached |
| Decreased appetite (loss of appetite) | 177 | 3.6 3.1–4.1ROR 3.7 · χ² 329 / p 1e-73 | 3.5 EB05 3.1 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 0.8 | no trial data cached |
| Respiratory disorder | 21 | 3.3 2.1–5.0ROR 3.3 · χ² 31 / p 1e-8 | 3.1 EB05 2.1 · IC025 +0.9 3/3 methods agree | Labeled (related wording) related wording | serious PRR 8.1 | no trial data cached |
| Mucosal inflammation | 18 | 3.2 2.0–5.1ROR 3.2 · χ² 26 / p 2e-7 | 3.0 EB05 2.0 · IC025 +0.8 3/3 methods agree | Labeled (related wording) related wording | serious PRR 6.0 | no trial data cached |
| Neutrophil count decreased | 27 | 3.1 2.1–4.5ROR 3.1 · χ² 37 / p 7e-10 | 3.0 EB05 2.2 · IC025 +0.9 3/3 methods agree | Lab value / disease marker | serious PRR 2.8 | no trial data cached |
| Neuropathy peripheral (nerve damage in hands/feet) | 63 | 3.1 2.4–4.0ROR 3.1 · χ² 89 / p 2e-21 | 3.1 EB05 2.5 · IC025 +1.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 1.6 | no trial data cached |
| Febrile neutropenia | 44 | 3.1 2.3–4.2ROR 3.1 · χ² 61 / p 3e-15 | 3.0 EB05 2.4 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 6.4 | no trial data cached |
| Herpes zoster (shingles) | 38 | 3.1 2.2–4.2ROR 3.1 · χ² 52 / p 3e-13 | 3.0 EB05 2.3 · IC025 +1.0 3/3 methods agree | Not in label — unassessed | serious PRR 7.3 | no trial data cached |
| Vomiting | 304 | 3.0 2.7–3.4ROR 3.2 · χ² 421 / p 9e-94 | 3.0 EB05 2.7 · IC025 +1.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 1.2 | no trial data cached |
| Bone marrow failure | 13 | 3.0 1.7–5.1ROR 3.0 · χ² 15 / p 5e-5 | 2.8 EB05 1.7 · IC025 +0.5 | Not in label — unassessed | serious PRR 4.8 | no trial data cached |
| Urticaria (hives) | 103 | 2.9 2.4–3.5ROR 2.9 · χ² 127 / p 1e-29 | 2.9 EB05 2.4 · IC025 +1.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 0.9 | no trial data cached |
| Septic shock | 24 | 2.6 1.7–3.9ROR 2.6 · χ² 22 / p 1e-6 | 2.5 EB05 1.8 · IC025 +0.6 | Not in label — unassessed | serious PRR 5.4 | no trial data cached |
| Full blood count decreased | 11 | 2.5 1.4–4.6ROR 2.6 · χ² 9 / p 0.001 | 2.4 EB05 1.4 · IC025 +0.2 | Lab value / disease marker | serious PRR 2.1 | no trial data cached |
| Pancytopenia (all blood cells low) | 30 | 2.5 1.8–3.6ROR 2.5 · χ² 26 / p 2e-7 | 2.5 EB05 1.8 · IC025 +0.7 | Labeled adverse reaction exact term | serious PRR 3.5 | no trial data cached |
| Leukopenia (low white blood cells) | 25 | 2.3 1.6–3.5ROR 2.3 · χ² 18 / p 1e-5 | 2.3 EB05 1.6 · IC025 +0.5 | Labeled adverse reaction exact term | serious PRR 2.8 | no trial data cached |
| Rash generalised | 13 | 2.3 1.3–4.0ROR 2.3 · χ² 8 / p 0.002 | 2.2 EB05 1.4 · IC025 +0.2 | Labeled (related wording) related wording | serious PRR 1.3 | no trial data cached |
| Mouth ulceration | 10 | 2.2 1.2–4.1ROR 2.2 · χ² 6 / p 0.009 | 2.1 EB05 1.2 · IC025 -0.0 PRR-only: not supported by EBGM or IC | Not in label — unassessed | serious PRR 1.8 | no trial data cached |
| Neoplasm progression | 16 | 2.1 1.3–3.5ROR 2.1 · χ² 8 / p 0.002 | 2.1 EB05 1.4 · IC025 +0.2 | Not in label — unassessed | serious PRR 3.8 | no trial data cached |
| Bone pain | 26 | 2.1 1.4–3.0ROR 2.1 · χ² 13 / p 1e-4 | 2.0 EB05 1.5 · IC025 +0.4 | Labeled (related wording) related wording | serious PRR 3.0 | no trial data cached |
Trial evidence (ClinicalTrials.gov)
Most frequently reported reactions
By raw co-report count, regardless of disproportionality. Common terms here are often the illness itself or generic outcomes.
| Reaction | Reports | PRR 95% CI · ROR · χ²/p | EBGM EB05 · IC025 | Label screen | Serious-only & strata | Trial cross-check |
|---|---|---|---|---|---|---|
| Nausea | 973 | 5.8 5.5–6.1ROR 7.1 · χ² 3,974 / p <1e-300 | 5.7 EB05 5.4 · IC025 +2.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 0.7 | no trial data cached |
| Fatigue (tiredness) | 829 | 5.0 4.7–5.3ROR 5.9 · χ² 2,739 / p <1e-300 | 5.0 EB05 4.7 · IC025 +2.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 0.6 | no trial data cached |
| Vomiting | 304 | 3.0 2.7–3.4ROR 3.2 · χ² 421 / p 9e-94 | 3.0 EB05 2.7 · IC025 +1.4 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 1.2 | no trial data cached |
| Constipation | 265 | 5.7 5.1–6.4ROR 6.0 · χ² 1,038 / p 4e-228 | 5.7 EB05 5.1 · IC025 +2.3 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 1.1 | no trial data cached |
| Platelet count decreased | 239 | 10.5 9.3–11.9ROR 11.0 · χ² 2,051 / p <1e-300 | 10.4 EB05 9.3 · IC025 +3.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 2.4 | no trial data cached |
| White blood cell count decreased | 229 | 9.9 8.7–11.2ROR 10.4 · χ² 1,824 / p <1e-300 | 9.8 EB05 8.7 · IC025 +3.1 3/3 methods agree | Labeled (related wording) related wording | serious PRR 4.6 | no trial data cached |
| Decreased appetite (loss of appetite) | 177 | 3.6 3.1–4.1ROR 3.7 · χ² 329 / p 1e-73 | 3.5 EB05 3.1 · IC025 +1.6 3/3 methods agree | Not in label — unassessed | serious PRR 0.8 | no trial data cached |
| Neutropenia (low neutrophils (infection-fighting cells)) | 132 | 4.6 3.8–5.4ROR 4.7 · χ² 365 / p 1e-81 | 4.5 EB05 3.9 · IC025 +1.9 3/3 methods agree | Not in label — unassessed | serious PRR 4.8 | no trial data cached |
| Blood count abnormal | 132 | 40.4 34.2–47.9ROR 41.6 · χ² 4,998 / p <1e-300 | 39.9 EB05 34.5 · IC025 +4.8 3/3 methods agree | Lab value / disease marker | serious PRR 9.8 | no trial data cached |
| Urticaria (hives) | 103 | 2.9 2.4–3.5ROR 2.9 · χ² 127 / p 1e-29 | 2.9 EB05 2.4 · IC025 +1.2 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 0.9 | no trial data cached |
| Thrombocytopenia (low platelets) | 100 | 4.2 3.5–5.1ROR 4.3 · χ² 241 / p 1e-54 | 4.1 EB05 3.5 · IC025 +1.7 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 3.0 | no trial data cached |
| Disease progression | 95 | 3.8 3.1–4.6ROR 3.8 · χ² 191 / p 9e-44 | 3.7 EB05 3.1 · IC025 +1.6 3/3 methods agree | Reporting / coding artifact | serious PRR 5.9 | no trial data cached |
| Neuropathy peripheral (nerve damage in hands/feet) | 63 | 3.1 2.4–4.0ROR 3.1 · χ² 89 / p 2e-21 | 3.1 EB05 2.5 · IC025 +1.2 3/3 methods agree | Labeled (related wording) related wording | serious PRR 1.6 | no trial data cached |
| Stomatitis (mouth sores) | 63 | 4.9 3.8–6.2ROR 4.9 · χ² 189 / p 2e-43 | 4.7 EB05 3.8 · IC025 +1.8 3/3 methods agree | Labeled adverse reaction exact term | serious PRR 4.4 | no trial data cached |
| Febrile neutropenia | 44 | 3.1 2.3–4.2ROR 3.1 · χ² 61 / p 3e-15 | 3.0 EB05 2.4 · IC025 +1.1 3/3 methods agree | Not in label — unassessed | serious PRR 6.4 | no trial data cached |
Unlabeled candidate signals
These flagged terms were not found in the FDA label text and do not match an artifact pattern. They are the pairs that would merit a structured assessment (temporality, dose-response, biological plausibility, consistency across databases, trial or cohort evidence). The screen has not done that; string-matching misses label wording, and a strong PRR can still be stimulated reporting, co-medication, or the disease itself.
- Hepatic cytolysis — n=42, PRR 16.1
- Myelodysplastic syndrome — n=28, PRR 9.1
- Nerve injury — n=21, PRR 8.8
- Neutropenia — n=132, PRR 4.6
- Decreased appetite — n=177, PRR 3.6
- Febrile neutropenia — n=44, PRR 3.1
- Herpes zoster — n=38, PRR 3.1
- Septic shock — n=24, PRR 2.6
Want to assess one of these properly? The runbook describes the Bradford Hill / trial-evidence workflow used on the assessment page, and handoff_top1000_signals.csv lists the strongest unassessed pairs across all drugs.
Common questions
What are the most reported side effects of Procarbazine?
In FDA FAERS, the most frequently co-reported reaction terms for Procarbazine are nausea, fatigue, vomiting, constipation, platelet count decreased, white blood cell count decreased. These are report counts, not rates: FAERS has no denominator, reporting is voluntary and uneven, and a term can be reported because of the illness being treated rather than the drug.
Does Procarbazine have an FDA boxed warning?
Yes. The current FDA label carries a boxed warning: It is recommended that MATULANE be given only by or under the supervision of a physician experienced in the use of potent antineoplastic drugs. Adequate clinical and laboratory facilities should be available to patients for proper monitoring of treatment.
Do FAERS signals prove that Procarbazine causes these side effects?
No. A disproportionality signal (PRR, ROR) means a reaction is reported more often with this drug than with others in the database. That can reflect a real effect, but also the disease being treated, stimulated reporting after news or litigation, co-medications, or how reports are coded. Causality needs temporality, dose-response, biological plausibility, consistency across data sources and, ideally, trial or cohort evidence. This page screens each term against the FDA label and ClinicalTrials.gov results; it does not establish causation.
Sources & methods
- FDA label via openFDA (set ID 1aa75a3a-18c9-49e1-91a6-293d0b7da756, effective 20240916; matched on
openfda.generic_name.exact:"PROCARBAZINE HYDROCHLORIDE") - Bayesian shrinkage measures computed offline over all 1,317,300 cached pairs: BCPNN information component (IC, with Norén closed-form IC025) and MGPS empirical-Bayes geometric mean (EBGM, EB05) with a two-component gamma prior fitted by maximum marginal likelihood (α₁=0.57, β₁=0.02, α₂=1.42, β₂=0.70, w=0.17); unstratified
- FAERS pair statistics from the OpenPV build of 2026-09-14 (openFDA
count=aggregation, fieldpatient.drug.openfda.generic_name.exact, 54 reaction terms, min 3 co-reports); PRR/ROR with 95% CI, chi-square with Yates correction - Serious-only and stratified counts (serious:1, patient.patientsex, primarysource.qualification) from openFDA count queries; serious-only PRR uses the drug serious report total and the term global serious total (N_serious=11,882,979); strata shown only when n ≥ 20
- Seriousness and sex counts from openFDA
count=serious,patient.patientsex,seriousnessdeath
Page generated 2026-10-08. Label and PubChem text are retrieved automatically and may lag the current label; always check the current prescribing information. OpenPV is a beta research tool of the Open Source Medicine Foundation.